Yarn drying apparatus



March 22, 1949. EWlNG 2,465,214

YARN DRYING APPARATUS Filed. 001;. 9. 1946 IN V EN TOR.

ALVIN LEWIN G BY m 7 ATT NEY Patented Mar. 22, 1949 2,465,214 YARN DRYING APPARATUS Alvin L. Ewing,

du Pont de Nemours & Company,

Richmond, Va., assignor to E. 1.

Wilmington,

DeL, a corporation of Delaware Application October 9, 1946, Serial No. 702,130

6 Claims.

This invention relates to the drying of yarns and more particularly to the drying of yarns while they are traveling on an advancing reel.

In processing individual or multiple ends of a yarn, such as viscose rayon, on an advancing reel, the yarn may be drawn directly from the spinning bath or it may be taken from bobbins or bucket cakes. In the absence of any liquid film or in the presence of a uniform liquid film between the individual turns, advancement of the yarn on the reel occurs with the individual turns apart and evenly spaced. Generally, washing and purification of the yarn is performed while the yarn is on the reel. For these steps, addition of liquid to the gel rayon on the reel is required and usually sufficient quantities of liquid are added to form a film. As long as the film is continuous, no unbalanced surface tension forces are present to cause convergence of the yarn into a bundle. When the uniform film is broken in an uncontrolled manner or when it becomes nonuniform, unbalanced surface tension forces result and these forces cause the individual strands to come together. For example, the gradual destruction of the film as the yarn sheet moves through a dryer circumferentially located around the reel results in unbalanced surface tension forces and an entanglement of the filaments occurs. Such adverse efiects occur also when the yarn ends are removed from the reel or in other instances in which the film removal is uncontrolled. Once in contact, it is extremely difiicult to separate the yarn ends for wind-up purposes. Means for preventing the formation of bundles of two or more threads is spinning processes.

Accordingly, an object of this invention is the provision of a method whereby the troublesome converging together of the yarn turns may be avoided. Another object is the provision of apparatus the use of which in conjunction with advancing reels permits the advancement of yarns without entanglement and snagging of the filaments. A still further object is the provision of apparatus for the removal of excess liquid from the yarn after wet-processing but prior to removal of the yarn from the reel or prior to dry-' ing by use of conventional drying apparatus. Other objects will appear hereinafter.

These objects are accomplished by the use of an absorbent belt, rotating in one position partially around the reel and in contact with the yarn sheet. As the sheet passes under the belt excess liquid is absorbed. The liquid-laden belt is moved from contact with the yarn on the reel to adjustdesirable for emcient able wringers at which point the liquid is removed and from which point the absorbent belt returns to the reel, the belt rotating continually in the same path and the filaments remaining in' the same position relative to each other. The absorbent belt holds the individual yarn turns apart and evenly spaced and simultaneously completely does Figure 1, an additional dryer 6 circumferontially arranged around the reel.

Referring to the drawings, an absorbent belt I is passed around an advancing reel 2, which is driven by any suitable source, the belt being in contact with the reel preferably for approximately 240, although the arc of contact depends on the diameter of the bottom roller 4 and length of the belt. The bottom roller 4 is free turning. The belt l is in contact with the yarn sheet 5 moving on the revolving reel. The wringer roller 3 presses against the bottom'roller 4, the belt passing through the nip. Roller 3 is spring loaded so that an adjustable means for various pressures is available to accommodate variations in thickness and composition of the belts. The bottom roller d turns because of the pressure of the wringer roller 3 and the rotation of the belt i. The rollers are adjusted at the proper angle so that the belt l rotates in one position on the reel 2 regardless of the advancement of the yarn sheet 5 passing under the belt i.

A fine grain regenerated cellulose sponge having a thickness of A inch and a width of 1 inches is cemented to a woven cotton tape of the same width and having a thickness of about ie inch. The belt so formed is placed on the reel so that the sponge surface is on the inside next to the yarn sheet. Preferably, the bottom roller 4 is mounted in a pivotable frame although this is not essential. Sufiicient tension is applied to the belt 1 to prevent slippage of the belt on theyarn sheet 5. The pivoting of the belt pulleys serves primarily to maintain a constant tension on the belt which expands or shrinks during the absorbing and wringing steps. The pivot arrangement is such that roller 4 may be canted in the vertical or horizontal plane with respect to the reel so that the belt rotates in the same path regardless of the advancement setting on the reel. Instead of a plvotable frame, it is possible to use rigidly mounted rollers in conjunction with guide means for keeping the belt running in one path.

In operation the belt rotates with the yarn sheet. As soaking wet yarn comes in contact with the belt, the excess liquid is absorbed thereby eliminating the liquid film bridging the space between adjacent yarns. The individual advancing helices of yarn are undisturbed in respect to each other, since they are held in place by the sponge resting against the yarn. Accordingly, destruction of the connecting film of liquid does not cause converging r entanglement of filaments. The liquid-laden belt then passes to and through thenip of liquid is removed. This liquid may be collected by any appropriate means, or it may be discarded,

depending upon its value. Generally, the liquid is predominantly water and the excess is carried away by drains properly situated. After wringing, the belt returns to the reel sufliciently dry to absorb more liquid and the process is thus continually repeated.

The sponge material may be composed of cellulosic material, natural sponge or any other equivalent substance. The thickness of the sponge may be varied. While the invention has been described in respect to a sponge having a thickness of inch, sponges of inch and inch thicknesses have been used and with greater success. The thicker sponges have greater absorbing power.

The reel used in the process described above can be any advancing reel which permits the necessary contact of the yarn and belt. the process and apparatus of this invention may be used in connection with such reels as are disclosed in Ewing, U. S. 2,287,517 and Ewing, U. S. 2,317,747. The periphery of the particular reel used was 43 inches and the reel was running at approximately 75 R. P. M. with inch advancement cycle. The number of threads being advanced and dried by the process and apparatus of this invention may be varied widely as from one to 50 or more. Ten to 24 ends have been simultaneously advanced and dried by this invention without encountering difiiculties in entanglement or converging of filaments of adjacent threads.

The yarn being advanced and dried may be of any denier. While the invention has referred particularly to viscose rayon, yarn and the like of cotton, silk, wool, polyamides or any other synthetic filaments or the like may be successfully treated by this invention. The belt may be used at any appropriate stage in the processing of any particular yarn. The apparatus and process of this invention is useful in the treatment of yarns or the like of polyvinyl alcohol, or other vinyl or acrylic polymers or interpolymers of cellulose derivatives such as its ethers and esters, of regenerated cellulose, of cellulose acetate, and of similar materials. In the treatment of viscose rayon this invention is particularly used advantageously in steps involving the washing of acid salts from the viscose rayon with Water as the yarn advances in the reel. However, the belt may be used in connection with desulfuring, bleaching and/or finishing of viscose rayon or the removal of other residual materials from any of the above yarns.

The supporting portion of the belt is normally made of woven cotton. The composite parts of the belt can, however, be composed of any material which is resistant to the particular liquid being removed and which, if necessary, can be together. For example,

satisfactorily bonded rollers 3 and 4, and the excess For example,-

v the use of vacuum or other materials which may be sed in making the belt are sponge rubber vulcanized to rubber, highly absorbent pile fabrics or woolen blankets having heavy naps. It is also possible to use cotton cloth belts, as for example, belts composed of canton flannel, without additional absorbent material.

The belt is generally positioned on the reel as is shown in Figures 1 and 2. However. the belt may be placed so that contact is made with the yarn on the underside of the reel or on either side of the cylindrical reel. Likewise, the rollers 3 and 4 or a plurality of them may be located at any place desired around the reel. However, in any arrangement the desired contact between the belt and the yarn sheet must be made and it is desirable to control the rotation of the belt so that it travels continually in substantially the same path. By proper adjustments of these factors, the yarn continues to advance helically both under the belt and beyond after excess liquid is removed. Undesirable contact of one helical pass of yarn with another is avoided by means of this invention whether single or multiple ends are being processed on the reel.

The apparatus of this invention is particularly useful in that it not only prevents the entangling and snagging of filaments but it permits a greater efliciency of operation of the reel. In the processing of viscose rayon the moisture content of the threads is greatly reduced by use of the invention. As they approach the belt I the filaments have about 400% to 500% moisture whereas, after passing under the belt, they have only about moisture. This substantial reduction in water content allows for a material reduction in power consumption by the dryer 6 which is generally arranged about the reel as shown in Figure 2. This dryer is normally electrically heated. By use of the apparatus of this invention, approximately a 50% reduction in power is attained, the same end condition being reached. Accordingly, the capacity of the dryer is greatly increased and a greater output of yarn per unit time is made possible.

Further reduction of moisture is possible by increasing the length of the belt or by passing it overheated rollers either prior to, during or subsequent to the wringing step. By such steps the belt can be placed in a dry or substantially dry state prior to its return to the reel. Further, the width of the belt can be increased with similar results. The moisture content of the yarn can be reduced to a very low percentage. of about 50% or less by these means or combinations of them. Likewise, it is within the scope of this invention to employ two or more belts. If multiple belts are used, successive ones can be heated to increasingly higher temperatures and complete drying of the yarn may be attained. The method of contact drying of this invention is far more eflicient than air drying.

While the description above has shown the use of a dryer circumferentially arranged about the reel, other drying means may be employed in conjunction with this invention. Thus, the use of heated air with or without forced circulation, the use of other contact dryers, such as heated metallic belts, may be employed at any appropriate stage in the processing of the yarn by this invention.

A further advantage of the apparatus and process of this invention lies in the fact that there is only negligible degradation of the yarn. There is a minimum of movement between the belt and the yarn. Since the belt is rolling with the yarn and the absorbent material is soft and rapidly becomes saturated with liquid, there is very little abrasion or wear on the filaments.

Any departure from the above description which conforms to the present invention is intended to be included within the scope of the claims.

I claim:

1. The process of drying filaments moving helically on advancing reels comprising continually removing liquid carried by said filaments by contacting them with an endless absorbent belt, the said belt absorbing the said liquid and simultaneously holding the said filaments in their positions relative to each other during helical advancement of said filaments under said belt.

2. The process comprising continually absorbing liquid carried by yarn filaments moving helically on advancing reels by passing a substantially dry absorbent belt up to and partially around said reels so that contact is made between the absorbent portion of the said belt and the said filaments, passing the said belt between two rollers after said contact so that liquid absorbed by the belt through said contact is removed and so that the belt rotates continually in the same path.

3. The process comprising continually absorbing liquid carried by yarn filaments moving helically on advancing reels by passing a substantially dry absorbent belt up to and partially around said reels so that contact is made between the absorbent portion of the said belt and the said filaments, passing the said belt between two pivoted rollers after said contact so that liquid absorbed by the belt through said contact is removed, adjusting the said rollers so that the belt rotates continually in the same path, the position of the said filaments relative to each other being maintained as they pass under and beyond the said belt.

4. Yarn treating apparatus comprising an endless absorbent belt moving so that contact is the said reel and means for 6 made with liquid-carrying cally on an advancing reel, the said belt absorbing liquid at the area of said contact while keeping the said yams in position relative to each other during helical advancement of said yarns under said belt, means for removing at a point distant from the said reel said liquid absorbed by the said belt and means for directing the said belt continually in the same path.

5. Yarn treating apparatus comprising an endless absorbent belt moving so that contact between liquid-carrying yarns travelling helically on an advancing reel and absorbent portions of the belt is being continually made, the said belt absorbing the said liquid and simultaneously holding the said yarns in their positions relative to each other during helical advancement of said yarns under said belt.

6. Yarn treating apparatus comprising an endless absorbent belt; means for directing the path of the said belt so that contact between liquidcarrying yarns travelling helically on an advancing reel and absorbent portions of the belt is being continuously made, the said belt absorbing the said liquid and simultaneously holding the said yarns in their positions relative to each other during helical advancement of said yarns under said belt; means for removing the liquid absorbed by the said belt at a point distant from directing the said belt continually in the same path.

. ALVIN L. EWING.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS yarns travelling heli- Number Name Date 491,545 Gerard Feb. 14, 1893 1,240,468 Martin Sept. 18, 191'! 1,983,795 Furness Dec. 11,, 1934 2,355,391 Nelson et al. Aug. 8, 1944 

